Modeling of the influence of dielectric target on interface sheath characteristics in a radio-frequency magnetron sputtering

The differences in the plasma structure and particularly in the sheath profile between metallic and dielectric targets in an rf magnetron plasma were investigated. A typical magnetron sputtering system driven at 13.56 MHz for both metallic and dielectric targets was numerically studied using a hybrid model. The magnet unit consisting of a pair of inner and outer magnets and a yoke behind the target, generated a ring shaped permanent magnetic field in the discharge space. The results show that marked double minima in the dielectric erosion profile was caused by the existence of the charging on the dielectric material during ion sputtering process.